def add_two_numbers(a, b, c=10)
    return a + b

print(add_two_numbers(10,20))

def is_prime(n):
	    if n <= 1:
	        return False
	    for i in range(2, int(n**0.5) + 1):
             if n % i == 0:
	            return False
	    return True

	# for i in range(1, 101):
	#     print(i)
	#
	# print(i)

print(is_prime(23))

	# 递归实现阶乘
def factorial(n):
	    if n == 0:
	        return 1
	    else:
	        return n * factorial(n - 1)

	print(factorial(5))